Electric switch



Feb. 21, 1933. H J LY 1,898,443

ELECTRIC SWITCH 2 Sheets-Sheet l !I!llllllllllllliiillllllllii Filed Nov. 4, 1930 mumm \ I; I INVENTOR Herman J H n: erly,

Feb. 21, 1933. H, J HAMMERLY 1,898,443

' ELECTRIC SWITCH Filed Nov. 4, 1930 2 Sheets-Sheet 2 Fig. .5- 1O 20 14 I5 Patented Feb. 21, 1933 l UNITED STATES PATENT orrlcs HERMAN J. HAMHEBLLY, OF WALLINGFORD, CONNECTICUT, ASSIGNOB TO TBUNB'ULI.

ELECTRIC MANUFACTURING COMPANY, OF .PLAINVILLE, CONNECTICUT, A CORPO- RATION OF CONNECTICUT ELEc'rnIc swrrcn J Application filed November 4, 1980. Serial No. 493,329.

My invention relates to electric switches of the class commonly used in the industrial cuits, etc., andwhich class of switches are usuallyenclosed in metal boxes and provided with suitable external operating handles.

My present construction is similar in general to the construction disclosed in my Patent 1,824,137 and the particular-objects of my invention are to provide a construction in which each of the respective stationary contacts is positioned in a recess in the base in such a manner that a solid bodyof insulation is interposed bet-ween the members of each pair of stationary contacts an'dbetween the bent ends of each" of the movable contacts and in which construction the contact making portions (or ends) of the movable contacts are movable in perforations in the insulating base'so that, at the time of moving away from engagement with the stationary contacts, each of the contact making ends of the movable contacts Wlll be enclosed in a perforation of approximately equal dimensions and in such a manner as to greatly reduce the air space ad aCent the circuit breaking points. It has; been found in practice that this construction etfectually blocks the are from pole to pole or to any adjacent metal parts and the limited air space tends to smother such an are as might start to form. Another object is to incorporate the aforementioned features in a-switch in which the circuit is simultaneously broken at two points in each pole of the circuit to be controlled.

Another obiect is to provide aswitch which will safely control a circuit far inexcess of the load usually controlled by a switch of like proportions.

In carrying out my invention I empldy a pair of stationary contacts, a movable switch blade and pertinent terminals for a single pole switch or for each pole of a multiple circuit.

I have shown in the drawings, a single pole anda double pole switch, but obviously my invention may be applied to any reasonable number of circuit poles and each unitmay be a single pole switch or all of the units -may be mounted upon a single base. arts for controlling lighting or power an 1 Fig.1 is a plan view of a double unit embodying the contact members for one side of the circuit and showing in the dot and dash lines a conventional enclosing box and switch in the open circuit position.

Fig. 3 is an exploded perspective View of the stationary contacts and the movable switch member.

Fig. dis a perspective view showing a slight modification 0f the movable switch member.

Fig. 5 is a plan view of a single unit with a modified form of base and embodying one of the'stationary contacts omittingthe movable switch member.

Fig. 6 is a side View and partial section of the form of device shown in Fig. 5 with the movable switch member in place in the open circuit position. i

Fig. 7 is an end View and partially transverse section of the insulating base of the device in Figs. 5 and 6.

Fig. 8 is a sectional contacts .closed. p x .The insulating body or base 10 may be made of any suitable material and will usually be housed in a box or receptacle 11, indicated by the dot and dash lines in Fig. 1, although this is no part of my present invention. The base will, of course, be seview showing the cured inplace in some suitable manner, as a 16 and nuts 17 which may also secure the circuit terminals '18 in place.

The,base is provided with recesses-20 into which the contacts 14 project. These recesses are preferably in the form of perforations or passages extending, through the insulation. The lower face of the base is provided with a transverse passage 21 in which the operating rod or crank 22 is movable.

The movable switch member has two contact arms 23 which are spaced apart from each other and adapted to slide in the perforations 20 and engage the contacts 14.

These arms 23 are connected by a bar 2% which is preferably integral with the arms;

in fact the bar and arms may be readily formed from a single strip or stamping of sheet copper or bronze, bent or otherwise formed into the proper shape.

This movable switch member is secured to an insulating carrier 25, for instance, by means of a number of rivets 26. The carrier may conveniently be formed of insulating fiber or the like and is guided to slide in grooves 27 in the base at the edges of the opposite walls of the passage 21. These grooves 27 are connected at their outer ends by a transverse groove 28. which permits the outer end of the carrier .25 and the cross bar 24 of the switch member to slide far enough to bring the arms 23 into engagement with the contacts 14:, and leavethe base closed at 29 over the ends of the carrier and the crossbar as shown in Figs. 1 and 5. 1

To close the circuit the movable switch member and carrier are moved in any suitable manner so as to bring the arms 23 into engagement with the contacts 14.

To open the circuit the movable switch member is actuated in any suitable manner either by an ordinary hand actuated crank or by suitable quick break mechanism (not shown). It will be seen that the circuit breaking points are located in the perforations 20, 20 in the insulating base and that the circuit is broken within the perforations and at two points spaced apart from each other a considerable distance. It will be particularly notedthat the space between the passages or perforations 20--2O at the top of the base is entirely closed by insulating material. This makes it impossible for an for an arc to jump to part.

The movable switch member is preferably bent into U shape form asshown but may be formed in any suitable manner. It will be seen that the form shown in Fig. 4 has a cross-bar 24 narrower than the contact arms 23'.

In the form shown in Figs. 5, 6 and 7 the insulating base 10 is provided with feet or lugs 30 by means of which it may conveniently be mounted.

. I claim:

1. In an electric switch an insulating base, stationary contacts carried thereby and spaced. apart from each other, said base having perforations in which said contacts are located and a movable switch member having spaced apart contact arms guided in said perforations, said base having an insulating barrier interposed between said arms when the switch is in open circuit position, said arms being connected by a cross-bar and said base being closed over the cross bar between the stationary contacts.

2. An electric switch including an insulatany adjacent metal ing base, stationary contacts carried thereby and spaced apart from each other, said base having perforationsin which said contacts are located and a movable switch member having an insulating carrier and spaced apart contact arms, said base having an integral insulating barrier interposed between said perforations, said arms being connected by a cross-bar, said base being closed over arms when the switch is in open circuit position, said arms being connected by a crossbar, said base being closed over said ,crossbar between the stationary contacts and said base having guide grooves for the carrier. HERMAN J. HAMMERLY.

arc to jump out of the openings and across from one contact to the other as the circuit is beingbrokeni This closure also minimizes the possibility of accidental engagement with the contacts. As the contact making ends of the movable arms 23 are enclosed or guided between the insulating walls. of the base in the perforations 20, 20 at the time the circuit is being broker? any are which tends to form will be instant snuffed out and the insulating barriers make. it practically impossible 

